1. Field of the Invention
The present invention relates to a vehicle, particularly to a vehicle in which a battery pack is disposed outside the vehicle cabin.
2. Description of the Related Art
There has been known a vehicle (so-called electric vehicle or hybrid vehicle) provided with a battery pack including a plurality of battery modules. If a hybrid vehicle is taken as an example, a typical hybrid vehicle is known to have a structure in which a battery pack is disposed on the back of the rear seat or below the luggage space.
Such a structure of a hybrid vehicle has a problem in that the presence of the battery pack reduces the trunk space behind the rear seat. In addition, the typical hybrid vehicle has a problem in that weight distribution of the vehicle in the fore-and-aft direction thereof is difficult to be adjusted due to the weight of the battery pack.
Thus, in recent years, there has been proposed a hybrid vehicle in which the battery pack is disposed below the center in the fore-and-aft direction of the vehicle, i.e., below the floor panel of the vehicle. For example, Japanese Unexamined Patent Application Publication (JP-A) No. 2000-247261 discloses a structure of the vehicle floor, in which the battery is disposed below the floor panel of the vehicle.
In addition, there has been proposed a technology for cooling a battery by supplying power from a power source for driving a vehicle or a power source for auxiliary machinery and rotating a fan for cooling the battery (JP-A No. 4-312304).
In the case of a FWD or 4WD vehicle which needs a propeller shaft, and in which a battery is installed below the floor panel of the vehicle, a plurality of batteries need to be disposed on both sides of the propeller shaft in the vehicle width direction.
In the above configuration, the battery may directly receive heat from an engine or a radiator at the front of the vehicle while the vehicle is being driven. Application of a heat insulating structure for heat damage prevention to each of a plurality of batteries disposed on both sides of the propeller shaft causes a significant increase in weight and cost.